Planarization of semiconductor devices

ABSTRACT

In certain embodiments, a method for processing a substrate includes applying a surface treatment to selected surfaces of the substrate. The substrate has a non-planar topography including structures defining recesses. The method further includes depositing a fill material on the substrate by spin-on deposition. The surface treatment directs the fill material to the recesses and away from the selected surfaces to fill the recesses with the fill material without adhering to the selected surfaces. The method further includes removing the surface treatment from the selected surfaces of the substrate and depositing a planarizing film on the substrate by spin-on deposition. The planarizing film is deposited on the selected surfaces and top surfaces of the fill material.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/860,359, filed on Jun. 12, 2019, which application is incorporated byreference.

BACKGROUND OF THE INVENTION

This disclosure relates generally to microfabrication, and, in certainembodiments, to planarization of semiconductor devices.

Microfabrication includes various steps of depositing, patterning,modifying, and removing materials from a wafer. Processing to buildintegrated circuits involves multiple film coatings deposited onpatterned topography but with a goal of providing a planar top surface.Depositing a film on a surface with patterned topography benefitssubsequent processes. For example, exposing a photolithographic patternin a layer of photoresist is more successful when exposing on a planarlayer of photoresist, or a planar underlayer such as an anti-reflectivecoating (ARC).

SUMMARY

In certain embodiments, a method for processing a substrate includesreceiving a substrate having a non-planar topography includingstructures defining recesses. The method further includes depositing aself-assembled monolayer (SAM) on top surfaces of the structures of thesubstrate, without depositing the SAM on surfaces located below the topsurfaces of the structures of the substrate. The SAM provides adewetting surface condition for a particular fill material. The methodfurther includes depositing the particular fill material on thesubstrate by spin-on deposition such that the particular fill materialfills the recesses without adhering to the SAM. The method furtherincludes removing the SAM and depositing a planarizing film on thesubstrate by spin-on deposition. The planarizing film is deposited onthe top surfaces of the structures and on top surfaces of the particularfill material that fills the recesses.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure, and theadvantages thereof, reference is now made to the following descriptionstaken in conjunction with the accompanying drawings, in which:

FIGS. 1A-1B illustrate a cross-sectional view of an example process ofdepositing a planarizing film on a semiconductor device in whichincomplete planarization occurs;

FIGS. 2A-2B illustrate a cross-sectional view of an example process ofdepositing a planarizing film on a semiconductor device in whichincomplete planarization occurs;

FIGS. 3A-3E illustrate a cross-sectional view of an examplesemiconductor device at various stages of a process for depositing aplanarizing film, according to certain embodiments of this disclosure;

FIGS. 4A-4E illustrate a cross-sectional view of an examplesemiconductor device at various stages of a process for depositing aplanarizing film, according to certain embodiments of this disclosure;

FIGS. 5A-5E illustrate cross-sectional views of an example semiconductordevice at various stages for depositing a planarizing film, according tocertain embodiments of this disclosure;

FIGS. 6A-6B illustrate example details of an example self-assembledmonolayer, according to certain embodiments of this disclosure;

FIG. 7 illustrates an example method for forming a semiconductor device,according to certain embodiments of this disclosure;

FIG. 8 illustrates an example method for forming a semiconductor device,according to certain embodiments of this disclosure; and

FIG. 9 illustrates an example method for forming a semiconductor device,according to certain embodiments of this disclosure.

DETAILED DESCRIPTION

Non-planar surfaces may cause yield issues for subsequent steps in asemiconductor fabrication process. As just one example, lithographicimaging is generally used as part of a process to pattern surfaces of asemiconductor device during fabrication. Lithography is used to createdesired patterns in an underlying layer, and can includephotolithography, electron beam lithography, extreme ultravioletlithography, and other types of lithography. However, when a resistimage lies on top of a non-planar layer (e.g., potentially non-planardue to varied topography of a layer that underlies the non-planarlayer), the pattern may be distorted after development due to variationsin thickness of the resist image because of the undulations in thesurface on which the resist was deposited. These distortions may impactcritical dimension and other aspects of fabrication.

Achieving a planarized film when the film is deposited over surfaceshaving varied topography, leading to a film having a varied topographyitself, is difficult. As semiconductor devices have shrunk,planarization has become even more difficult due, at least in part, toattendant increased variations in topography within a smaller area of awafer undergoing fabrication. For example, decreasing technology nodesdown to 5 nm node and beyond continue to exacerbate planarizationproblems. Furthermore, long-range planarization (e.g., planarizationover an area greater than 5 μm) of spin-on-carbons, spin-on-dielectrics,metal oxides, bottom anti-reflective coatings frequently experienceincomplete planarization over varied topography, with the resulting filmthickness bias exceeding acceptable levels.

One conventional technique to planarize topography is usingchemical-mechanical polishing (CMP). While CMP may be useful for somestages of microfabrication, at other stages CMP may present certainproblems due to its harsh nature or relatively high cost.

Planarizing by spin-on deposition, also known as spin-on coating, may bedesired at some stages of microfabrication. Planarizing by spin-oncoating, however, can be very challenging, particularly in certainapplications. Deviations in film thicknesses for spin-on films depositedover topography often drive downstream processing beyond appropriatespecifications necessitating actions to control the planarization offilms.

Unit operations having errors introduced due to deviations in filmthickness height include, for example, lithographic critical dimensionchanges due to reflectivity, lithographic focus control, etch depth, andsubsequent deposition processes. Additionally, novel three-dimensionalapplications and processes such as pattern reversals and exhumingmaterials post spacer processes may call for stringent levels of filmthickness control over topography.

Thus, where appropriate, semiconductor fabrication processes ofteninclude steps designed to planarize one or more surfaces of asemiconductor, at one or more stages of the semiconductor fabricationprocess, to a desired extent or as much as possible.

Embodiments of this disclosure provide improved techniques forplanarizing a film deposited over a substrate having a variedtopography. Embodiments of this disclosure include applying a surfacetreatment (e.g., a self-assembled monolayer) to selected surfaces of asubstrate that has a varied topography (including structures that definerecesses). For example, the surface treatment may be applied to topsurfaces of the substrate and not to surfaces of the substrate in therecesses. The surface treatment creates a surface condition in which theparticular fill material is less likely to (or does not) form on theselected surfaces of the substrate that include the surface treatment(e.g., the top surfaces of the substrate) and is directed to anddeposited on other surfaces of the substrate to which the surfacetreatment has not been applied (e.g., surfaces in the recesses). As anexample, the surface treatment may be described as creating a dewettingsurface condition on the top surfaces of the substrate to direct theparticular fill material to the recesses, which are “wettable” relativeto the particular fill material.

The particular fill material is then deposited and fills the recesses inthe substrate, “pre-filling” the recesses prior to a subsequentdeposition of a planarizing film. The particular fill material may bedeposited such that the top surfaces of the substrate and the depositedparticular fill material in the recesses provides an effectively planarsurface. In certain embodiments, after removing the surface treatmentand any other suitable layers (e.g., a hardmask), a planarizing film isdeposited (e.g., an organic film deposited using a spin-on depositionprocess) on the effectively planar surface of the substrate resultingfrom depositing the particular fill material in the recesses, which hasimproved planarization relative to films deposited using conventionaltechniques.

Embodiments of this disclosure include spin-on planarization methodsincorporating use of surface selective monolayers. Spin-on surfaceselective monolayers may have reasonable processing times and an abilityto control film dewetting relative to a surface to which the surfaceselective monolayer has not been applied. Embodiments of this disclosureinclude adhering surface selective monolayer(s) to a hardmask surface toguide a spin-on film into recesses of a given substrate topography, suchas trench areas. This initial spin-on film can fill in topography up toa top surface of the substrate. Then a second spin-on film is depositedto finish planarizing the substrate. Multiple different materials can beused in embodiments of this disclosure. Such techniques can improveplanarization by spin-on deposition and can reduce processing cost andincrease yield.

FIGS. 1A-1B illustrate a cross-sectional view of an example process ofdepositing a planarizing film on a semiconductor device 100 in whichincomplete planarization occurs. As shown in FIG. 1A, semiconductordevice 100 includes a substrate 102, which may be a portion of asubstrate of a larger device (e.g., wafer or semiconductor wafer)undergoing microfabrication.

Substrate 102 has a non-planar topography that includes structures 104defining recesses 106. Although a particular number of structures 104and recesses 106 are illustrated, this disclosure contemplatessubstrates like substrate 102 including any suitable number ofstructures 104 and recesses 106. Throughout this disclosure, structuresof substrates (e.g., structures 104 and structures described below withreference to other figures) also may be referred to as raised regions.Although this disclosure primarily describes “recesses,” it will beappreciated that other suitable features might be formed in asemiconductor layer, including (whether or not considered “recesses”)lines, holes, open areas, trenches, vias, and/or other suitablestructures, using embodiments of this disclosure. Recesses (e.g,recesses 106 or other recess of this disclosure) may be formed, forexample, by building up structures (e.g., structures 104 or otherstructures of this disclosure) on underlying layers and/or by etchingmaterial from one or more layers.

Substrate 102 may include top surfaces 108, which also may be referredto as top surfaces 108 of structures 104 of substrate 102. Recesses 106may include surfaces 110, such as sidewall surfaces 110 a and bottomsurfaces 110 b. Surfaces 110 of recesses 106 may be considered to belocated below top surfaces 108 of structures 104 of substrate 102.

Substrate 102, including structures 104 of substrate 102, can be of anysuitable material, such as organic hardmasks, oxides, nitrides,dielectrics, barrier materials, or conducting materials. In a particularexample, substrate 102 includes silicon dioxide.

FIG. 1B illustrates a cross-sectional view of semiconductor device 100after a planarizing film 112 has been deposited on substrate 102. In oneexample, planarizing film 112 is deposited using a spin-on depositionprocess; however, this disclosure contemplates planarizing film 112being deposited in any suitable manner. In certain embodiments,planarizing film 112 includes an organic material, such as a spin-oncarbon; however, this disclosure contemplates planarizing film 112including any suitable material.

With spin-on planarization, a particular material (e.g., the material ofplanarizing film 112) is deposited on a substrate (e.g., substrate 102).The substrate is then rotated (if not already rotating, possibly at arelatively low velocity) at a relatively high velocity so thatcentrifugal force causes deposited material to move toward edges of thesubstrate, thereby coating the substrate. Excess material is typicallyspun off the substrate.

When a given topology or relief pattern has regions of densely arrangedstructures (e.g., from the left of FIGS. 1A and 1B, the first fourrecesses 106) this density can push deposition material upward andmanipulate a mass fraction of how much material can go into recesses. Inregions of sparsely arranged or populated features (for example, wherethere is an isolated line without other features nearby) (e.g., theright-most recess 106 in FIGS. 1A and 1B), the deposited material cansettle down into these larger pockets such that a final depositedz-height will track with the percent open regions. While these problemscan exist at technology nodes of various sizes, these problems can beexacerbated as technology nodes continue to shrink, where the width ofrecesses 106 become even smaller and the features more densely packed,creating increased topography variations in an even tighter space.

FIG. 1B illustrates an example result of a spin-on deposition ofplanarizing film 112, with film z-height variations over areas of thetopography of substrate 102. For example, a top surface 114 ofplanarizing film 112 is non-planar. It should be understood that thechanging topography of planarizing film 112 as shown in FIG. 1B ismerely an example, and that actual changes in topography may vary fromdeposition to deposition, even with a substrate having a similartopography to the topography of substrate 102.

FIGS. 2A-2B illustrate a cross-sectional view of an example process ofdepositing a planarizing film on a semiconductor device 200 in whichincomplete planarization occurs. As shown in FIG. 2A, semiconductordevice 200 includes a substrate 202, which may be a portion of asubstrate of a larger device (e.g., wafer or semiconductor wafer)undergoing microfabrication.

Substrate 202 has a non-planar topography that includes structures 204defining recess 206. Although a particular number of structures 204 andrecesses 206 are illustrated, this disclosure contemplates substrateslike substrate 202 including any suitable number of structures 204 andrecesses 206. Throughout this disclosure, structures 204 also may bereferred to as raised regions.

Structures 204 and recess 206 of substrate 202 form what may beconsidered a three-dimensional feature (e.g., a three-dimensionaltrench). Simultaneously filling and planarizing such structures withminimal processing steps can be difficult. Such structures varydepending on application but can have considerable size variations,possibly on the order of microns wide or deep.

Substrate 202 may include top surfaces 208, which also may be referredto as top surfaces 208 of structures 204 of substrate 202. Recess 206may include surfaces 210, such as sidewall surfaces 210 a and bottomsurfaces 210 b. In the illustrated example, sidewall surfaces 210 acreate a stepped sidewall of recess 206, incrementally increasing,moving from the bottom of recess 206 to the top of recess 206, a widthof recess 106. Surfaces 210 of recess 206 may be considered to belocated below top surfaces 208 of structures 204 of substrate 202.

Substrate 202, including structures 204 of substrate 202, can be ofsimilar materials as substrate 102.

FIG. 2B illustrates a cross-sectional view of semiconductor device 200after a planarizing film 212 has been deposited on substrate 202. In oneexample, planarizing film 212 is deposited using a spin-on depositionprocess similar to the spin-on process described above with reference toFIGS. 1A-1B; however, this disclosure contemplates planarizing film 212being deposited in any suitable manner. In certain embodiments,planarizing film 212 includes an organic material, such as a spin-oncarbon; however, this disclosure contemplates planarizing film 212including any suitable material.

FIG. 2B illustrates an example result of a spin-on deposition coatingwith film z-height variations over areas of topography. For example, atop surface 214 of planarizing film 212 is non-planar. It should beunderstood that the changing topography of planarizing film 212 as shownin FIG. 2B is merely an example, and that actual changes in topographymay vary from deposition to deposition, even with a substrate having asimilar topography to the topography of substrate 202. While theseproblems can exist at technology nodes of various sizes, these problemscan be exacerbated as nodes continue to shrink below the 10 nm node size(e.g., down to the currently possibly 5 nm node size), where the widthof recesses 106 become even smaller and the features more denselypacked, creating increased topography variations in an even tighterspace.

As can be seen from FIGS. 1A-1B and FIGS. 2A-2B, merely depositing aplanarizing film on a substrate that has a varied topography may lead tothe film having incomplete planarization, which can negatively affectsubsequent steps of the fabrication process.

FIGS. 3A-3E illustrate a cross-sectional view of an examplesemiconductor device 300 at various stages of a process for depositing aplanarizing film, according to certain embodiments of this disclosure.As described in greater detail below, the example process of FIGS. 3A-3Eincludes applying a surface treatment to selected surfaces of asubstrate of semiconductor device 300 and depositing a planarizing filmin multiple deposition steps.

As shown in FIG. 3A, semiconductor device 300 is largely similar tosemiconductor device 100 in FIG. 1A and includes a substrate 302, whichmay be a portion of a substrate of a larger device (e.g., wafer orsemiconductor wafer) undergoing microfabrication. Substrate 302,structures 304, recesses 306, top surfaces 308, surfaces 310 aregenerally analogous to substrate 202, structures 204, recesses 206, topsurfaces 208, and surfaces 210, the descriptions of which areincorporated by reference without being repeated.

FIGS. 3B-3C illustrate stages of the process for depositing aplanarizing film on substrate 302 in which a surface treatment isapplied to selected surfaces of substrate 302 and in which recesses 306of substrate 302 are filled (partially or entirely) with a fillmaterial. That is, rather than proceeding to depositing a planarizingfilm on substrate 302 (as was the case with substrate 102 in FIGS.1A-1B), a surface treatment is first applied to selected surfaces ofsubstrate 302, and recesses 306 of substrate 302 are filled (partiallyor entirely) with a fill material to provide an underlying topographythat is more planar than the topography illustrated in FIGS. 3A-3B.

In the illustrated example, as shown in FIG. 3B, a surface condition 316exists on top surfaces 308 of substrate 302, and a surface condition 318exists on surfaces 310 of recesses 306.

A surface having surface condition 316 (top surfaces 308 of substrate302 in the illustrated example) tends to repel or otherwise directcertain fill materials, such as the particular fill material to bedeposited in FIG. 3C, away from the surface having surface condition316. Surface condition 316 also may be referred to as a dewetting stateor dewetting surface condition. In certain embodiments, surfacecondition 316 provides a high hydrophobicity mechanism that directscertain fill materials away from surfaces that have surface condition316. In a dewetting state, the surface contact angle may be matched foroptimum solute/solvent dewetting for a particular fill material, such asthe fill material to be deposited in FIG. 3C.

A surface having surface condition 318 (surfaces 310 of recesses 306 inthe illustrated example) tends to bond with or even attract certain fillmaterials, such as the particular fill material to be deposited in FIG.3C, to the surface having surface condition 318. Surface condition 318also may be referred to as a wettable state. In a wettable state, thesurface contact angle may be matched for optimum solute/solventwettability for a particular fill material, such as the fill material tobe deposited in FIG. 3C.

One or both of surface condition 316 and surface condition 318 may becreated by applying a surface treatment to the surface(s) of substrate302 at which those conditions exist. The surface condition of a surfaceof substrate 302 also may be referred to as the surface energy of thesurface, such that changing the surface condition of a surface changesthe surface energy of the surface.

For example, to provide selected surfaces (e.g., top surfaces 308) ofsubstrate 302 with surface condition 316, a surface treatment may beapplied to surfaces of substrate 302 targeted to have surface condition316. The surface treatment creates a dewetting surface conditionrelative to a particular fill material (the fill material to bedeposited in FIG. 3C) and may be deposited on top surfaces 308 ofsubstrate 302 to direct the fill material away from the surfaces towhich the surface treatment has been applied (top surfaces 308 ofsubstrate 302). In certain embodiments, applying the surface treatmentto top surfaces 308 of substrate 302 includes depositing aself-assembled monolayer (SAM) on top surfaces 308 of substrate 302.SAMs are described in greater detail below.

As another example, to provide selected surfaces (e.g., surfaces 310) ofsubstrate 302 with surface condition 318, a change to a surfacecondition of the selected surfaces might or might not be appropriate. Incertain embodiments, the material at the selected surfaces (e.g.,surfaces 310 of recesses 306) may have been selected to be wettablerelative to a particular fill material (the fill material to bedeposited in FIG. 3C), or the particular fill material (the fillmaterial to be deposited in FIG. 3C) may have been selected because thematerial at the selected surfaces (e.g., surfaces 310 of recesses 306)is wettable relative to that particular fill material without additionalprocessing of the surface of substrate 302. In certain embodiments,surfaces of substrate 302 at which deposition of the fill material isdesired, however, may be treated to facilitate deposition of the fillmaterial at those surfaces.

As shown in FIG. 3C, fill material 320 is deposited in recesses 306 oversurfaces 310 of recesses 306, surfaces which have surface condition 318.As fill material 320 is deposited, surface condition 316 of top surfaces308 of substrate 302 directs fill material 320 to recesses 306 and awayfrom top surfaces 308 to fill recesses 306 with fill material 320without adhering to surfaces that have surface condition 316 (topsurfaces 308). In certain embodiments, the combination of surfacecondition 316 on selected surfaces of substrate 302 (e.g., top surfaces308 of substrate 302) and surface condition 318 on other surfaces ofsubstrate 302 (e.g., surfaces 310 in recesses 306 of substrate 302)promotes deposition of fill material 320 in recesses 306, withoutdepositing fill material 320 on the selected surfaces (e.g., topsurfaces 308) of substrate 302.

Throughout this disclosure, reference is made to a fill material (e.g.,fill material 320 and other fill materials described with reference toother figures below) filling a recess or recesses (e.g., recesses 306 orother recesses described with reference to other figures below). Thisdisclosure contemplates the fill material partially filling recesses,exactly filling recesses with no overflow or underflow, or overfillingrecesses.

Fill material 320 may include any suitable material and may be depositedusing a particular solute/solvent combination. As just a few examples,fill material 320 may be a photo resist, a silicon-containinganti-reflective coating, a spin-on organic carbon, or a spin-ondielectric. In the case of a photoresist, a photoresist may includeseveral components, including but not limited to a polymer backbone,solvent, photo acid generator (PAG), and base quencher. Example basepolymers may include Novolac Resin, Poly methyl methacrylate, andPoly(Styrene)-B-Poly(4-Hydroxystyrene).

Spin-on carbon or organic materials may be used in a patterning processto optimize optical reflection, planarization, and/or etch resistance.Typical formulas are often highly aromatic (AR) and contain crosslinkingcomponents. Polystyrene is an example of an aromatic, high carboncontent spin-on polymer. In an example of spin-on dielectric, a spin-ondielectric may be a functional, silicon-containing, inorganic polymermaterial. A particular example spin-on dielectric is Polysilazane. Incertain embodiments, fill material 320 is deposited using a spin-ondeposition process. As just one example, fill material 320 may be anorganic material deposited using a spin-on deposition process, such as aspin-on carbon.

As shown in FIG. 3C, after deposition of fill material 320, fillmaterial 320 may substantially fill recesses 306 such that top surfaces308 of substrate 302 and top surfaces 322 of fill material 320collectively provide a substantially planar surface for subsequentdeposition of a planarizing film. The surface treatment (e.g., adeposited SAM) that creates surface condition 316 (e.g., a dewettingsurface condition) for top surfaces 308 of substrate 302 directs fillmaterial 320 to recesses 306 without depositing fill material 320 on topsurfaces 308 of substrate 302. Directing fill material 320 to recesses306 allows fill material 320 to reduce and potentially eliminate atleast a portion of the variation in topography present in substrate 302(e.g., the variation in topography shown in FIGS. 3A-3B). Deposited fillmaterial 320 in recesses 306 provides an improved (and potentiallygenerally flat) surface for depositing a planarizing film in asubsequent deposition step rather than depositing the planarizing filmon the varied topography of substrate 302 shown in FIGS. 3A-3B.

As shown in FIG. 3D, top surfaces 308 of substrate 302 and top surfaces322 of fill material 320 both have surface condition 318. In certainembodiments, to accomplish both top surfaces 308 and top surfaces 322having surface condition 318 (e.g., a wettable condition relative to aplanarizing film to be deposited), the surface treatment applied to theselected surfaces of substrate 302 (top surfaces 308 of substrate 302)in FIG. 3B is removed. Any suitable process may be used to remove thesurface treatment from the selected surfaces of substrate 302.

As shown in FIG. 3E, a planarizing film 324 is deposited on substrate302. Planarizing film 324 may include any suitable material. In certainembodiments, the material of planarizing film 324 is the same materialas the material of fill material 320; however, this disclosurecontemplates fill material 320 and planarizing film 324 includingdifferent materials. Due at least in part to the improved planarity ofsubstrate 302 after fill material 320 has been deposited (e.g., as shownin FIG. 3C) relative to the varied topography of substrate 302 shown inFIG. 3A, a top surface 326 of planarizing film 324 has an improvedplanarity. For example, top surface 326 of planarizing film 324 has animproved planarity relative to top surface 114 of planarizing film 112in FIG. 1B.

Planarizing film 324 may be deposited in any suitable manner. In certainembodiments, planarizing film 324 is deposited using a spin-ondeposition process. For example, planarizing film 324 may include anorganic material. As a particular example, planarizing film 324 may be aspin-on carbon. Planarizing film 324 may be deposited to a desiredthickness that is appropriate for a particular implementation.

Following the deposition of planarizing film 324, which has improvedplanar characteristics, additional features of semiconductor device 300may be formed in layers above or below planarizing film 324. As just afew examples, these features may include metal lines, vias, or othersuitable features. Due to the improved planar characteristics ofplanarizing film 324, subsequently patterned features showed improveddimensional control and ultimately improved downstream yield.

FIGS. 4A-4E illustrate a cross-sectional view of an examplesemiconductor device 400 at various stages of a process for depositing aplanarizing film, according to certain embodiments of this disclosure.As described in greater detail below, the example process of FIGS. 4A-4Eincludes applying a surface treatment to selected surfaces of asubstrate of semiconductor device 400 and depositing a planarizing filmin multiple deposition steps.

Semiconductor device 400, as illustrated in FIG. 4A, is analogous andlargely similar to semiconductor device 300, as illustrated in FIG. 3A;however, semiconductor device 400 includes a hardmask 409. Semiconductordevice 400 includes a substrate 402, which is analogous to substrate 302and may include similar structures and materials, descriptions of whichare not repeated. Substrate 402, structures 404, recesses 406, topsurfaces 408, surfaces 410 are generally analogous to substrate 302,structures 304, recesses 306, top surfaces 308, and surfaces 310, thedescriptions of which are incorporated by reference without beingrepeated.

Semiconductor device 400 includes hardmask 409, which may include anysuitable material, and may have been used to form recesses 406. Asexamples, hardmask 409 may include a resist layer, a spin-on carbonlayer, an amorphous carbon layer (whether or not deposited using aspin-on deposition process), a silicon nitride layer, a silicon dioxidelayer, a metal-containing layer, or any other suitable type of hardmask.Although described as a hardmask, hardmask 409 could be any suitabletype of deposited film, such as a resist layer.

In certain embodiments, hardmask 409 is relatively thin, such as, forexample, 2 nm to 20 nm, relative to an underlying layer (e.g.,underlying portions of substrate 402). Hardmask 409 has a top surface411. Subsequent to formation of recesses 406, and as shown in FIG. 4A,hardmask 409 may be located at top surfaces 408 of structures 404 ofsubstrate 402, which also may be referred to as top surfaces 408 ofsubstrate 402. Although shown as a separate layer in FIG. 4, hardmask409 may be a separate layer formed on top surfaces 408 of substrate 402or could be included in substrate 402, such that substrate 302 in FIGS.3A-3E could include hardmask as a top layer. Thus, for purposes of thisdisclosure, top surface 411 of hardmask 409 could also be considered atop surface of substrate 402.

FIGS. 4B-4C illustrate stages of the process for depositing aplanarizing film on substrate 402 in which a surface treatment isapplied to selected surfaces of substrate 402 and in which recesses 406of substrate 402 are filled (partially or entirely) with a fillmaterial. That is, rather than proceeding to depositing a planarizingfilm on substrate 402 (as was the case with substrate 102 in FIGS.1A-1B), a surface treatment is first applied to selected surfaces ofsubstrate 402, and recesses 406 of substrate 402 are filled (partiallyor entirely) with a fill material to provide an underlying topographythat is more planar than the topography illustrated in FIGS. 4A-4B.

In the illustrated example of FIG. 4B, a surface treatment 416 isapplied to top surfaces 411 of hardmask 409 (which also may beconsidered top surfaces of substrate 402), and surface treatment 416 isnot applied to surfaces 410 of recesses 406 of substrate 402. Surfacetreatment 416 creates surface condition 316 in which a surface havingsurface condition 316 (e.g., top surfaces 411 of hardmask 409 in theillustrated example) tends to repel or otherwise direct certain fillmaterials, such as the particular fill material to be deposited in FIG.4C, away from the surface having surface condition 316.

Surfaces 410 in recesses 406 of substrate 402 may have a surfacecondition analogous to surface condition 318 a surface having surfacecondition 318 tends to bond with or even attract certain fill materials,such as the particular fill material to be deposited in FIG. 4C, to thesurface having surface condition 318.

In certain embodiments, surface treatment 416 is a SAM deposited tocreate surface condition 316 for surfaces on which the SAM is deposited.For example, to provide selected surfaces of substrate 402 (e.g., topsurfaces 411 of hardmask 409) with surface condition 316 (a dewettingstate for the fill material to be deposited in FIG. 4C), surfacetreatment 416 may be applied to surfaces of substrate 402 targeted tohave surface condition 316 to direct the fill material away from thesurfaces to which surface treatment 416 has been applied.

In certain embodiments, applying surface treatment 416 to top surfaces411 of hardmask 409 includes depositing a SAM on top surfaces 411 ofhardmask 409. As a particular example, the SAM may be a liquid phaseself-assembled monolayer. Although described as a monolayer, one ofskill in the art will appreciate that complete coverage of surfacetreatment 416 might or might not be achieved and that aspects of thisdisclosure can still be accomplished. In other words, perfect alignmentof the SAM (or other suitable surface treatment) is not required, assolute/solvent dewetting can occur without complete monolayer alignment.A given surface-selective monolayer has a terminal molecular groupdesigned to cause dewetting of the spun on material.

Surface treatment 416 may be applied in any suitable manner. In certainembodiments, surface treatment 416 (e.g., SAM) is deposited throughspin-on techniques or a low temperature chemical vapor deposition (CVD)process. For example, a particular surface treatment 416 (e.g., SAM) maybe deposited on selected surfaces of substrate 402 (e.g., top surfaces411 of hardmask 409). The applied surface treatment 416 may be selectiveto a particular underlying material, so that the surface treatment 416is applied to particular surfaces and not others. For example, surfacetreatment 416 may be selective to the material of hardmask 409, so thatsurface treatment 416 is deposited on top surface 411 of hardmask 409and not on surfaces 410 of recesses 406. The particular process stepsand chemistry for depositing surface treatment may vary depending on thesurface treatment, surface to which the surface treatment is beingapplied, and the deposition technique.

Surface treatments, including self-assembled monolayers (SAMs), may beapplied to purely polycrystalline surfaces and to other types of organicmaterials or liquids. Surface treatment 416 may be tuned for adherenceto particular substrates and to provide particular functionality (e.g,liquid dewetting) for various applications. Liquid phase SAMs may beable to selectively and significantly change wetting properties ofsurfaces such as metals (e.g. copper), hardmasks, oxides, organicsurfaces, and other dielectrics, to name just a few examples.

As shown in FIG. 4C, fill material 420 is deposited in recesses 406 oversurfaces 410 of recesses 406, surfaces to which surface treatment 416has not been applied and which generally have a surface conditionanalogous to surface condition 318. As fill material 420 is deposited,surface treatment 416 of top surfaces 411 of hardmask 409 directs fillmaterial 420 to recesses 406 and away from top surfaces 411 to fillrecesses 406 with fill material 420 without adhering to surfaces towhich surface treatment 416 has been applied (e.g., top surfaces 411 ofhardmask 409). In certain embodiments, the combination of surfacetreatment 416 on selected surfaces of substrate 402 (e.g., top surfaces411) and a lack of surface treatment 416 on other surfaces (e.g.,surfaces 410 in recesses 406) promotes deposition of fill material 420in recesses 406, without depositing fill material 420 on the selectedsurfaces of substrate 402.

Fill material 420 is generally analogous to fill material 320, thedetails of which are incorporated by reference.

Furthermore, in certain embodiments, depending for example, on thetopography of substrate 402, including the depth of recesses 406 and theselected fill material 420 and associated deposition technique, one ormultiple deposition steps may be executed until reaching a desired filllevel. In certain embodiments, fill material 420 is deposited using aspin-on deposition process. As just one example, fill material 420 maybe an organic material deposited using a spin-on deposition process,such as a spin-on carbon.

As shown in FIG. 4C, after deposition of fill material 420, fillmaterial 420 may substantially fill recesses 406 such that top surfaces408 of substrate 402 and top surfaces 422 of fill material 420collectively provide a substantially planar surface for subsequentdeposition of a planarizing film. As described above, surface treatment416 (e.g., a deposited SAM) creates surface condition 316 for topsurfaces 411 of hardmask 409, directing fill material 420 to recesses406 without depositing fill material 420 on top surfaces 411 of hardmask409. Directing fill material 420 to recesses 406 allows fill material420 to reduce and potentially eliminate at least a portion of thevariation in topography present in substrate 402 (e.g., the variation intopography shown in FIGS. 4A-4B). Deposited fill material 420 inrecesses 406 provides an improved (and potentially generally flat)surface for depositing a planarizing film in a subsequent depositionstep rather than depositing the planarizing film on the variedtopography of substrate 402 shown in FIGS. 4A-4B.

In a particular example, with a SAM bonded to a surface of substrate 402(e.g., a top surface 411 of hardmask 409), a particular fill material420 solute/solvent can be used for spin-on deposition. For spin-ondeposition, the particular fill material 420 may be deposited onsubstrate 402, and substrate 402 may then be rotated to spread theparticular fill material 420 across the surface of substrate 402,potentially evenly. With the SAM adhered to top surfaces 411 of hardmask409, top surfaces 411 of hardmask 409 have a surface energy thatessentially repels the particular fill material 420. After spin-coatingthe particular fill material 420, the particular fill material 420 fillsrecesses 406, creating an approximately planar surface, without beingdeposited on top surfaces 411 of hardmask 409. The particular fillmaterial 420 (e.g., a particular polymer) can be selected based ondewetting properties of a selected surface treatment 416 (e.g., SAM), ora particular surface treatment 416 (e.g., a particular SAM) can beselected based on a desired fill material 420 (e.g., a particularpolymer).

As shown in FIG. 4D, surface treatment 416 and hardmask 409 have beenremoved from semiconductor device 400. In certain embodiments, in one ormore etch stops, surface treatment 416 and hardmask 409 are removed byany suitable combination of a wet solvent strip, a wet etch, a plasmaetch, or a UV/O₂ treatment. This disclosure contemplates any suitabletype of removal process for removing surface treatment 416 and hardmask409.

FIG. 4D shows semiconductor device 400 after deposition of fill material420 and removal of surface treatment 416 and hardmask 409. The removalprocess used to remove surface treatment 416 and hardmask 409 leavesfill material 420 in recesses 406 of substrate 402. In certainembodiments, an etchant used in one or more etch steps to remove surfacetreatment 416 and hardmask 409 is selective to surface treatment 416and/or hardmask 409, and does not etch (or etches only a minimal amountof) fill material 420. As a result, recesses 406 are filled with fillmaterial 420, such that top surfaces 408 of substrate 402 and topsurfaces 422 of fill material 420 together form an essentially planarsurface.

In certain embodiments, recesses 406 become somewhat over filled, as aresult of the deposition process used to deposit fill material 420 inFIG. 4C. This over filled condition may appear as an elevation overrecesses 406 as the fill material 420 fills, but dewets from surfacesthat have surface treatment 416 (e.g., top surfaces 411 of hardmask409). This small overfilled region may be absorbed in subsequentdepositions (e.g., during deposition of a planarizing film, as describedbelow with reference to FIG. 4E), or could be removed by an etch step orCMP, if desired. This overburden deposition and removal process can beused to reduce or eliminate instances in which fill material 420 doesnot completely fill recesses 406.

In FIG. 4D, both top surfaces 408 of substrate 402 and top surfaces 422of fill material 420 have a surface condition analogous to surfacecondition 318 (e.g., wettable with respect to planarizing film to bedeposited in a subsequent step).

As shown in FIG. 4E, a planarizing film 424 is deposited on substrate402. FIG. 4E is generally similar to FIG. 3E, with references to fillmaterial 320, planarizing film 324, top surface 326 being replaced byreferences to fill material 420, planarizing film 424, top surface 426,respectively, along with other suitable analogous substitutions ofanalogous elements. Thus, the above description of FIG. 3E and itsassociated advantages is incorporated by reference with being repeated.

With recesses 406 of substrate 402 already filled (or mostly filled orslightly overfilled) with fill material 420, the varied topography ofsubstrate 402 that was present in FIGS. 4A and 4B has been reduced oreliminated, and a second spin-on deposition step for depositingplanarizing film 424 can more effectively planarize above substrate 402to a desired thickness level now that there is minimal z-heightdeviation.

With substrate 402 planarized, additional microfabrication steps can beexecuted. For example, following the deposition of planarizing film 424,which has improved planar characteristics, additional features ofsemiconductor device 400 may be formed in layers above or belowplanarizing film 424. As just a few examples, these features may includemetal lines, vias, or other suitable features. Due to the improvedplanar characteristics of planarizing film 424, subsequently patternedfeatures tend to have improved dimensional control and ultimatelyimproved downstream yield.

FIGS. 5A-5E illustrate cross-sectional views of an example semiconductordevice 500 at various stages for depositing a planarizing film,according to certain embodiments of this disclosure. As described ingreater detail below, the example process of FIGS. 5A-5E includesapplying a surface treatment to selected surfaces of a substrate ofsemiconductor device 500 and depositing a planarizing film in multipledeposition steps. The example process of FIGS. 5A-5E, which incorporatesthe use of a surface treatment to modify a surface condition of one ormore portions of a substrate, can provide an improved ability toplanarize a film (e.g., a spin-on carbon) deposited over an extendedrecessed region as part of an etchback process.

As shown in FIG. 5A, in the illustrated example, semiconductor device500 includes a substrate 502, which may be a portion of a substrate of alarger device (e.g., wafer or semiconductor wafer) undergoingmicrofabrication. Substrate 502 has a non-planar topography thatincludes a raised region 504 and a recessed region 505 having a recess506. Although a particular number of raised regions 504 and recessedregions 505/recesses 506 are illustrated, this disclosure contemplatessubstrates like substrate 502 including any suitable number of raisedregions 504 and recessed regions 505/recesses 506. Raised region 504also may be referred to as a structure.

Substrate 502 may include top surface 508, which also may be referred toas top surface 508 of raised region 504 of substrate 502. Recessedregion 505/recess 506 may include surfaces 510 a and 510 b. As anexample, surface 510 a may be considered a sidewall surface (as shown inFIG. 5B) and surface 510 b may be considered a bottom surface. Surfaces510 a and 510 b may be considered to be located below top surface 508 ofsubstrate 502.

Substrate 502 can be of any suitable material, such as organichardmasks, oxides, nitrides, dielectrics, barrier materials, orconducting materials. In a particular example, substrate 302 includessilicon, silicon dioxide, silicon nitride, and/or silicon oxynitride.

A hardmask 512 has been deposited on substrate 502. In certainembodiments, hardmask 512 is a spin-on carbon or other organic materialthat has been deposited using a spin-coating technique. As examples,hardmask 512 may include a resist layer, a spin-on carbon layer, anamorphous carbon layer (whether or not deposited using a spin-ondeposition process), a silicon nitride layer, a silicon dioxide layer, ametal-containing layer, or any other suitable type of hardmask. Althoughthis disclosure primarily describes hardmask 512 being a particularmaterial deposited using a particular technique, this disclosurecontemplates hardmask 512 being including any suitable material andbeing deposited using any suitable technique. Furthermore, althoughdescribed as a hardmask, hardmask 512 could be a resist or othersuitable type of layer.

As shown in FIG. 5B, an etchback has been performed on hardmask 512,removing hardmask 512 over top surface 508 of raised region 504 ofsubstrate 502, from a portion of surface 510 a of recessed region 505(such that at least a portion of hardmask 512 is located below topsurface 508), and from a portion 511 a of surface 510 b of recessedregion 505. The etchback of hardmask 512 is performed using any suitablecombination of a wet solvent strip, a wet etch, a plasma etch, or aUV/O₂ treatment.

In certain embodiments, after performing the etchback of hardmask 512,semiconductor device 500 may be washed (e.g., using a solvent to removeoxidized surfaces resulting from the etchback of hardmask 512) to removecertain surface elements resulting from the etchback. In a particularexample, the solvent used to wash semiconductor device 500 is N-butylacetate; however, this disclosure contemplates using any suitable typeof solvent.

As can be seen at indicator 515, after performing the etchback, a dropin hardmask 512 can occur, meaning that hardmask terminates earlier thanintended and no longer has a planar (or generally planar) surface 513,which can cause problems with later fabrication steps.

FIGS. 5C-5D illustrate stages of a process for depositing a planarizingfilm on substrate 502 in which a surface treatment is applied toselected surfaces of substrate 502 and in which recessed region505/recess 506 are filled (partially or entirely) with a fill material.That is, rather than proceeding to depositing a planarizing film onsubstrate 502, a surface treatment is first applied to selected surfacesof substrate 502 and recessed region 505/recess 506 of substrate andthen recessed region 505/recess 506 is filled (partially or entirely)with a fill material to provide an underlying topography that is moreplanar than the topography illustrated in FIG. 5B, for example.

In the illustrated example, as shown in FIG. 5C, a surface treatment 516is applied to top surface 508 of substrate 502 and to a portion ofsurface 510 b of recessed region 505. In certain embodiments, theportion of surface 510 b of recessed region 505 to which surfacetreatment 516 is applied includes the entirety of portion 511 a;however, surface treatment 516 may be applied to a different portion(e.g., less than portion 511 a) of surface 510 b of recessed region 505.In the illustrated example, surface treatment 516 is not applied to asurface 513 of hardmask 512. Surface treatment 516 generally correspondsto surface treatment 416 described above with reference to FIGS. 4A-4E,although surface treatment 516 may be tuned to the particular substrate502 and fill material used for the process described with reference toFIGS. 5A-5E. Surface treatment 516 creates surface condition 316, acondition in which a surface having surface condition 316 (e.g., topsurface 508 and portion 511 a of surface 510 b) tends to repel orotherwise direct certain fill materials, such as the particular fillmaterial to be deposited in FIG. 5D, away from the surface havingsurface condition 316. In a dewetting state, the surface contact anglemay be matched for optimum solute/solvent dewetting for a particularfill material, such as the fill material to be deposited in FIG. 5D.

Surface 513 of hardmask 512 in recessed region 505 may have a surfacecondition analogous to surface condition 318, which, as described above,in which a surface having surface condition 318 (e.g., surface 513 ofhardmask 512) tends to bond with or even attract certain fill materials,such as the particular fill material to be deposited in FIG. 5D, to thesurface having surface condition 318. In a wettable state, the surfacecontact angle may be matched for optimum solute/solvent wettability fora particular fill material, such as the fill material to be deposited inFIG. 5D.

In certain embodiments, surface treatment 516 is a SAM deposited tocreate surface condition 316 for surfaces on which the SAM is deposited.For example, to provide selected surfaces of substrate 502 (e.g., topsurface 508 of substrate 502 and portion 511 a of surface 510 b ofrecessed region 505) with surface condition 316, surface treatment 516may be applied to surfaces of substrate 502 targeted to have surfacecondition 316. Surface treatment 516 creates a dewetting surfacecondition relative to a particular fill material (the fill material tobe deposited in FIG. 5D) and may be deposited on top surface 508 ofsubstrate 502 and portion 511 a of surface 510 b of recessed region 505to direct the fill material away from the surfaces to which surfacetreatment 516 has been applied (top surface 508 of substrate 502 andportion 511 a of surface 510 b of recessed region 505).

In certain embodiments, applying surface treatment 516 to top surface508 of substrate 502 and portion 511 a of surface 510 b of recessedregion 505 includes depositing a SAM on top surface 508 of substrate 502and portion 511 a of surface 510 b of recessed region 505. As aparticular example, the SAM may be a liquid phase SAM. In certainembodiments, depending on the materials of substrate 502 (at exposedsurfaces of substrate 502) and hardmask 512, surface treatment 516(e.g., a SAM) is specific to an oxide, nitride, or other suitablematerial.

Although described as a monolayer, one of skill in the art willappreciate that complete coverage of surface treatment 516 might ormight not be achieved and that aspects of this disclosure might still beaccomplished. In other words, perfect alignment of the SAM (or othersuitable surface treatment) is not required, as solute/solvent dewettingcan occur without complete monolayer alignment. A givensurface-selective monolayer has a terminal molecular group designed tocause dewetting of the spun on material. SAMs are described in greaterdetail below.

Surface treatment 516 may be applied in any suitable manner. In certainembodiments, surface treatment 516 is deposited through spin-ontechniques. For example, a particular surface treatment 516 (e.g., SAM)may be deposited on selected surfaces (e.g., top surface 508 ofsubstrate 502 and portion 511 a of surface 510 b of recessed region 505)of substrate 502. The applied surface treatment 516 may be selective toa particular underlying material, so that the surface treatment 516 isapplied to particular surfaces and not others. For example, surfacetreatment 516 may be selective to the material of substrate 502, so thatsurface treatment 516 is deposited on top surface 508 of substrate 502and portion 511 a of surface 510 b of recessed region 505 and not onsurface 513 of hardmask 512.

As shown in FIG. 5D, fill material 520 is deposited in recessed region505 over surface 513 of hardmask 512, surfaces to which surfacetreatment 516 has not been applied and which generally have a surfacecondition analogous to surface condition 318. As fill material 520 isdeposited, surface treatment 516 of top surface 508 of substrate 502 andportion 511 a of surface 510 b of recessed region 505 directs fillmaterial 520 to surface 513 of hardmask 512 and away from top surface508 of substrate 502 and portion 511 a of surface 510 b to fill recessedregion 505 over surface 513 of hardmask 512 with fill material 520without adhering to surfaces to which surface treatment 516 has beenapplied. In certain embodiments, the combination of surface treatment516 on selected surfaces (e.g., top surface 508 of substrate 502 andportion 511 a of surface 510 b of recessed region 505) and a lack ofsurface treatment 516 on other surfaces (e.g., surface 513 of hardmask512) promotes deposition of fill material 520 over surface 513 ofhardmask 512 in recessed region 505, without depositing fill material520 on the selected surfaces of substrate 502.

Fill material 520 is generally analogous to fill material 320 and fillmaterial 420, the details of which are incorporated by reference.

Furthermore, in certain embodiments, depending for example, on thetopography of substrate 502, including the depth of recessed region 505and the selected fill material 520 and associated deposition technique,one or multiple deposition steps may be executed until reaching adesired fill level.

Fill material 520 might or might not include the same material ashardmask 512. In certain embodiments, fill material 520 is depositedusing a spin-on deposition process. As just one example, fill material520 may be an organic material deposited using a spin-on depositionprocess, such as a spin-on carbon.

As shown in FIG. 5D, after deposition of fill material 520, fillmaterial 520 may fill at least a portion of recessed region 505 and mayhave a top surface 521 that is substantially planar. Surface treatment516 creates surface condition 316 for top surface 508 of substrate 502and portion 511 a of surface 510 b of recessed region 505, directingfill material 520 to surface 513 of hardmask 512 in recessed region 505without depositing fill material 520 on top surface 508 of substrate 502and portion 511 a of surface 510 b of recessed region 505. Directingfill material 520 to surface 513 of hardmask 512 allows fill material520 to reduce and potentially eliminate at least a portion of the dropin hardmask 512 that can occur over extended region, such as in recessedregion 505.

In a particular example, with a SAM bonded to surfaces of substrate 502(e.g., top surface 508 of substrate 502 and portion 511 a of surface 510b of recessed region 505), a particular fill material 520 solute/solventcan be used for spin-on deposition. For spin-on deposition, theparticular fill material 520 may be deposited on substrate 502, andsubstrate 502 may then be rotated to spread the particular fill material520 across the surface of substrate 502, potentially evenly. With theSAM adhered to top surface 508 of substrate 502 and portion 511 a ofsurface 510 b of recessed region 505, top surface 508 and portion 511 aof surface 510 b have a surface energy that essentially repels theparticular fill material 520. After spin-coating the particular fillmaterial 520, the particular fill material 520 accumulates over surface513 of hardmask 512, creating an approximately planar top surface 521,without being deposited on top surface 508 of substrate 502 and portion511 a of surface 510 b of recessed region 505. The particular fillmaterial 520 (e.g., a particular polymer) can be selected based ondewetting properties of a selected surface treatment 516 (e.g., SAM), ora particular surface treatment 516 (e.g., a particular SAM) can beselected based on a desired fill material 520 (e.g., a particularpolymer).

In certain embodiments, fill material 520 accumulates over surface 513of hardmask 512, creating a generally flat top surface 521. Depositedfill material 520 over surface 513 of hardmask 512 provides an improved(and potentially generally flat) surface for depositing a planarizingfilm in a subsequent deposition step rather than depositing theplanarizing film on the varied topography of substrate 502 shown inFIGS. 5A-5B and over the drop in hardmask 512 shown at indicator 515 inFIG. 5B.

If appropriate, after deposition of fill material 520, a short etchbackmay be performed on fill material 520 to achieve a desired thicknessand/or profile of fill material 520. In certain embodiments, theetchback of fill material 520, if executed, is performed using anysuitable combination of a wet solvent strip, a wet etch, a plasma etch,or a UV/O₂ treatment.

As shown in FIG. 5E, surface treatment 516 has been removed fromsemiconductor device 400 and a planarizing material 524 has beendeposited. In certain embodiments, surface treatment 516 is removed,using one or more etch steps, by any suitable combination of a wetsolvent strip, a wet etch, a plasma etch, or a UV/O₂ treatment. Thisdisclosure contemplates any suitable type of removal process forremoving surface treatment 516. The removal process used to removesurface treatment 516 leaves fill material 520 over surface 513 ofhardmask 512. In certain embodiments, an etchant used in one or moreetch steps to remove surface treatment 516 is selective to surfacetreatment 516, and does not etch (or etches only a minimal amount of)fill material 520. As a result, top surface 521 of fill material 520retains its relatively planar characteristic.

After removal of surface treatment 516, both top surface 508 ofsubstrate 502 and portion 511 a of surface 510 b of recessed region 505return to a surface condition analogous to surface condition 318 (e.g.,of FIG. 3D). That is, top surface 508 of substrate 502 and portion 511 aof surface 510 b of recessed region 505 may be considered wettable withrespect to a planarizing film to be deposited (e.g., planarizing film524).

As shown in FIG. 5E, a planarizing film 524 is deposited on substrate502. The material of planarizing film 524 may be any suitable material.In certain embodiments, the material of planarizing film 524 is the samematerial as the material of fill material 520 (which also may be thesame material as hardmask 512); however, this disclosure contemplatesfill material 520 and planarizing film 524 including differentmaterials. Due at least in part to the improved planarity of top surface521 in FIG. 5D after fill material 520 has been deposited, a top surface526 of planarizing film 524 has improved planarity.

Planarizing film 524 may be deposited in any suitable manner. In certainembodiments, planarizing film 524 is deposited using a spin-ondeposition process. For example, planarizing film 524 may include anorganic material. As a particular example, planarizing film 524 may be aspin-on carbon. Planarizing film 524 may be deposited to a desiredthickness that is appropriate for a particular implementation.

With substrate 502 planarized, additional microfabrication steps can beexecuted. For example, following the deposition of planarizing film 524,which has improved planar characteristics, additional features ofsemiconductor device 500 may be formed in layers above or belowplanarizing film 524. As just a few examples, these features may includemetal lines, vias, or other suitable features. Due to the improvedplanar characteristics of planarizing film 524, subsequently patternedfeatures tend to have improved dimensional control and ultimatelyimproved downstream yield.

FIGS. 6A-6B illustrate example details of an example self-assembledmonolayer (SAM) 600, according to certain embodiments of thisdisclosure. The embodiments described with reference to FIGS. 6A-6B areprovided as examples only. This disclosure contemplates a SAM of anysuitable structure and materials. As described above, surface treatment416 and/or 516 may be implemented as a SAM, and SAM 600 provides anexample of such a SAM.

FIG. 6A illustrates an example self-assembled monolayer (SAM) element602 that is adhered to substrate 604. Substrate 604 could be, forexample, substrate 302, substrate 402, hardmask 409, or substrate 502.

SAM element 602 includes three generalized functionality groups 606, ahead group 606 a, a functional group 606 b, and a tail group 606 c. Inselecting the make-up of SAM element 602 (and thereby a SAM 600 thatincludes multiple SAM elements 602, as shown in FIG. 6B), the role ofeach of these generalized functionality groups 606 may be consideredsuch that an appropriate selection is made.

Head group 606 a, which also may be referred to as a ligand group, isadapted to adhere to substrate 604 to bond or otherwise adhere SAMelement 602 to substrate 604. Thus, a material of head group 606 acapable of and suitable for adhering to the material of substrate 604may be selected for head group 606 a.

Furthermore, the selection of a material for head group 606 a (incombination with a selection of materials to which SAM 600 is intendedto adhere and a selection of materials to which SAM 600 is not intendedto adhere) promotes adhesion of SAM 600 to particular layers and not toother particular layers. For example, a head group 606 a that is adaptedto adhere to top surfaces 411 of hardmask 409 but that is not adapted toadhere to surfaces 410 of substrate 402 in recesses 406 may be selected.As another example, a head group 606 a may be selected that is adaptedto adhere to top surface 508 of raised region 504 of substrate 502 andto portion 511 a of surface 510 b of recessed region 505 of substrate502, but that is not adapted to adhere to surfaces 513 of hardmask 512.This feature of head group 606 a allows for selective deposition of SAM600.

In particular examples, head group 606 a may include a thiol-containinghead group (e.g., octadecanethiol (ODT)) or a silicon-containing headgroup (e.g., octadecyltrichlorosilane (OTS) or Octadecylsiloxane (ODS)).In certain embodiments, to attach to an organic-containing substrate(e.g., spin-on carbon or amorphous carbon), head group 606 a may includealkene-containing molecules, which can form a covalent bond with C—Hterminated surface sites of a substrate layer. In certain embodiments,to attach to a silicon-containing substrate (e.g., Si, SiO₂, SiN, orSiON), head group 606 a may include silicon and may be, for example, OTSor ODS. In certain embodiments, to attach to a metal-containingsubstrate (e.g., copper, cobalt, ruthenium, or another suitable metal),head group 606 a may be a thiol-containing head group, such as ODT.

Functional group 606 b, which also may be referred to as a terminalgroup, is designed to optimize the surface condition 316 (e.g., adewetting surface condition) provided by SAM 600.

Tail group 606 c, which also may be referred to as a spacer, coupleshead group 606 a to functional group 606 b and provides a desiredspacing between head group 606 a and functional group 606 b.Furthermore, the length of tail group 606 c can be tuned to adjust thecontact angle for a particular material (e.g., fill material 320, 420,or 520). In certain embodiments, tail group 606 c is a chain ofmolecules, such as an alkane chain. Tail group 606 c may be an organicinterphase, and may provide a well-defined thickness of SAM 600, act asa physical barrier, and alter electrical conductivity and local opticalproperties, if appropriate.

Tail group 606 c may be optimized for a fill material to be deposited(e.g., fill material 320, 420, or 520). For example, in the case of afill material to be deposited using a spin-on coating technique, tailgroup 606 c may be optimized for the spin-on solvent associated with thespin-on coating technique to be used. As particular examples,carbon-containing or fluorine-containing tail groups may be used. Fororganic spin-on polymers, the choice of solvent may be particularlyimportant. For example, low vapor pressure and high contact angle may beeffective. As a particular example, toluene may be effective.

FIG. 6B illustrates a SAM 600 formed from multiple SAM elements 602adhered to a surface of a substrate 604.

FIG. 7 illustrates an example method 700 for forming a semiconductordevice, according to certain embodiments of this disclosure. Embodimentsof method 700 could be applied to any of the embodiments described inthis disclosure, as well as other suitable embodiments. The methodbegins as step 702.

At step 704, a surface treatment is applied to selected surfaces on asubstrate that has a non-planar topography that includes structuresdefining recesses. For example, the substrate may be substrate 302,which includes structures 304 defining recesses 306, and the selectedsurfaces may be top surfaces 308 of substrate 302. As another example,the substrate may be substrate 402, which includes structures 404defining recesses 406, and the selected surfaces may be top surfaces 411of hardmask 409, which may be considered top surfaces of substrate 402.As yet another example, the substrate may be substrate 502, whichincludes raised region 504 and recessed region 505, and a selectedsurface may be top surfaces 508 of substrate 502. With respect tosubstrate 502, over the area of a particular wafer, substrate 502 mayinclude multiple raised regions 504 defining respective recesses 506. Incertain embodiments, applying the surface treatment at step 704 includesdepositing a SAM to the selected surfaces of the substrate.

At step 706, a fill material is deposited on the substrate, by spin-ondeposition for example. The surface treatment directs the fill materialto the recesses and away from the selected surfaces to fill the recesseswith the fill material without adhering to the selected surfaces.

For example, as described above with reference to FIGS. 3A-3E, fillmaterial 320 may be deposited on substrate 302, by spin-on depositionfor example, and the surface treatment that creates surface condition316 (e.g., a dewetting surface condition with respect to fill material320) directs fill material 320 to recesses 306 and away from topsurfaces 308 of substrate (to which the surface treatment that createssurface condition 316 has been applied) to fill recesses 306 withoutadhering to top surfaces 308 of substrate 302.

As another example, as described above with reference to FIGS. 4A-4E,surface treatment 416 creates a condition analogous to surface condition316 (e.g., a dewetting surface condition with respect to fill material420) and directs fill material 420 to recesses 406 and away from topsurfaces 411 of hardmask 409 (to which surface treatment 416 has beenapplied) to fill recesses 406 without adhering to top surfaces 411 ofhardmask 409.

In certain embodiments, such as described above with reference to FIGS.5A-5E, prior to applying surface treatment 516 to selected surfaces ofsubstrate 502 at step 704, hardmask 512 may be deposited on substrate502, and hardmask 512 may be etched to remove hardmask 512 over theselected surfaces of substrate 502 and from a portion of recess 506 (ofrecessed region 505), a portion of hardmask 512 remaining in recess 506(of recessed region 505). Depositing fill material 520 on substrate 502by spin-on deposition may include depositing fill material 520 on theportion of the hardmask 512 remaining in recess 506 (of recessed region505).

At step 708, the surface treatment is removed from the selected surfacesof the substrate. The surface treatment may be removed by any suitablecombination of a wet solvent strip, a wet etch, a plasma etch, or aUV/O₂ treatment. For example, the surface treatment that creates surfacecondition 316 may be removed from top surfaces 308 of substrate 302,surface treatment 416 (and possibly hardmask 409) may be removed fromtop surfaces 411 of hardmask 409, or surface treatment 516 may beremoved from top surface 508 of substrate 502 and from portion 511 a ofsurface 510 b of recess 506.

At step 710, a planarizing film is deposited on the substrate, byspin-on deposition for example. The planarizing film is deposited on theselected surfaces of the substrate and on top surfaces of the fillmaterial.For example, planarizing film 324, 424, or 524 may be depositedon substrate 302 (including on top surfaces 308 of substrate 302 and topsurface 322 of fill material 320 in recesses 306), on substrate 402(including on top surfaces 408 of substrate 402 and top surface 422 offill material 420 in recesses 406), or (on substrate 502 (including ontop surface 508 of substrate 502 and top surface 521 of fill material520 in recess 506), respectively.

Following the deposition of planarizing film, which has improved planarcharacteristics, additional features of the semiconductor device may beformed in layers above or below the planarizing film. As just a fewexamples, these features may include metal lines, vias, or othersuitable features. Due to the improved planar characteristics of theplanarizing film, subsequently patterned features tend to have improvedcritical dimension control and ultimately improved downstream yield.

At step 712, method 700 ends.

FIG. 8 illustrates an example method 800 for forming a semiconductordevice, according to certain embodiments of this disclosure. Embodimentsof method 800 could be applied to any of the embodiments described inthis disclosure, as well as other suitable embodiments. The methodbegins as step 802.

At step 804, a substrate having a non-planar topography includingstructures defining recesses is received. In certain embodiments, thesubstrate is received in a tool designed for depositing a surfacetreatment on selected surfaces of the substrate in a subsequent step.For example, the substrate may be substrate 302 (including structures304 defining recesses 306), substrate 402 (including structures 404defining recesses 406), or substrate 502 (including raised region 504and recessed region 505). Regarding substrate 502, over the area of aparticular wafer, substrate 502 may include multiple raised regions 504defining respective recessed regions 505/recesses 506. In certainembodiments, portions of the substrate include a hardmask such that topsurfaces of the portions of the substrate are the hardmask, as shown inFIG. 4A with hardmask 409 on substrate 402.

At step 806, a self-assembled monolayer (SAM) is deposited on topsurfaces of the structures of the substrate, without depositing the SAMon surfaces located below the top surfaces of the structures of thesubstrate. For example, the surface treatment that provides surfacecondition 316 (e.g., a SAM) may be deposited on top surfaces 308 ofsubstrate 302; surface treatment 416 (e.g., a SAM) may be deposited ontop surfaces 411 of hardmask 409, which may be considered top surfacesof substrate 402; or surface treatment 516 (e.g., a SAM) may bedeposited on top surface 508 of substrate 502, and potentially on othersurfaces of substrate 502, such as portion 511 a of surface 510 b ofrecessed region 505. In certain embodiments, the SAM provides adewetting surface condition (e.g., surface condition 316) for aparticular fill material (e.g., fill material 320, 420, or 520), such asthe fill material to be deposited at step 808. In certain embodiments,the SAM includes a head group (e.g., head group 606 a) coupled to thesubstrate, a functional group (functional group 606 b), and a tail group(e.g., tail group 606 c) that couples the head group to the functionalgroup such that that head group is spaced apart from the functionalgroup.

At step 808, the particular fill material is deposited on the substrate,by spin-on deposition for example, such that the particular fillmaterial fills the recesses without adhering to the SAM.

For example, as described above with reference to FIGS. 3A-3E, fillmaterial 320 may be deposited on substrate 302, by spin-on depositionfor example, and the surface treatment that creates surface condition316 (e.g., a dewetting surface condition with respect to fill material320) directs fill material 320 to recesses 306 and away from topsurfaces 308 of substrate (to which the surface treatment that createssurface condition 316 has been applied) to fill recesses 306 withoutadhering to the surface treatment that creates surface condition 316. Asanother example, as described above with reference to FIGS. 4A-4E,surface treatment 416 (e.g., a SAM) creates a condition analogous tosurface condition 316 (e.g., a dewetting surface condition with respectto fill material 420) and directs fill material 420 to recesses 406 andaway from top surfaces 411 of hardmask 409 (to which surface treatment416 has been applied) to fill recesses 406 without adhering to surfacetreatment 416.

In certain embodiments, as described with respect to FIGS. 5A-5E forexample, prior to depositing the SAM(surface treatment 516) on the topsurface (surface 508) of the structures of the substrate (raised region504 of substrate 502) at step 806, a hardmask 512 may be deposited onsubstrate 502 and hardmask 512 may be etched to remove hardmask 512 overthe top surface (surface 508) of the structures of the substrate (raisedregion 504 of substrate 502) and from a portion of recessed region505/recess 506, a portion of hardmask 512 remaining in recessed region505/recess 506. Depositing fill material 520 on substrate 502 by spin-ondeposition such that fill material 520 fills recess 506 (of recessedregion 505) without adhering to surface treatment 516 (e.g., a SAM) mayinclude depositing fill material 520 on the portion of hardmask 512remaining in recess 506 (of recessed region 505).

At step 810, the SAM is removed. For example, the SAM may be removed byany suitable combination of a wet solvent strip, a wet etch, a plasmaetch, or a UV/O₂ treatment. For example, as described above withreference to FIGS. 3A-3E, the surface treatment (e.g., a SAM) thatcreates surface condition 316 is removed from top surfaces 308 ofsubstrate 302. As another example, as described above with reference toFIGS. 4A-4E, surface treatment 416 (e.g., a SAM) is removed from topsurfaces 411 of hardmask 409. In certain embodiments, step 810 includesremoving hardmask 409. As another example, as described above withreference to FIGS. 5A-5E, surface treatment 516 (e.g., a SAM) is removedfrom top surface 508 of substrate 502 and from portion 511 a of surface510 b of recess 506 (of recessed region 505).

At step 812, a planarizing film is deposited on the substrate, byspin-on deposition for example. The planarizing film is deposited on thetop surfaces of the structures and on top surfaces of the particularfill material that fills the recesses. For example, planarizing film 324may be deposited on substrate 302 (including on top surfaces 308 ofsubstrate 302 and top surface 322 of fill material 320 in recesses 306),planarizing film 424 may be deposited on substrate 402 (including on topsurfaces 408 of substrate 402 and top surface 422 of fill material 420in recesses 406), or planarizing film 524 may be deposited on substrate502 (including on top surface 508 of substrate 502 and top surface 521of fill material 520 in recess 506 (of recessed region 505)).

Following the deposition of planarizing film, which has improved planarcharacteristics, additional features of the semiconductor device may beformed in layers above or below the planarizing film. As just a fewexamples, these features may include metal lines, vias, or othersuitable features. Due to the improved planar characteristics of theplanarizing film, subsequently patterned features tend to have improvedcritical dimension control and ultimately improved downstream yield.

At step 814, method 800 ends.

FIG. 9 illustrates an example method 900 for forming a semiconductordevice, according to certain embodiments of this disclosure. Embodimentsof method 900 could be applied to any of the embodiments described inthis disclosure, as well as other suitable embodiments. In thisparticular example, method 900 is described with reference tosemiconductor device 500 of FIGS. 5A-5E. The method begins as step 902.

At step 904, substrate 502 having a non-planar topography including araised region 504 and a recessed region 505 is received. For example,substrate 502 may be received in a tool for depositing a hardmask in asubsequent step, such as a spin-coating tool.

At step 906, hardmask 512 may be deposited on substrate 502.

At step 908, hardmask 512 is etched to remove hardmask 512 over topsurface 508 of raised region 504 of substrate 502 and from a portion 511a of a surface 510 b of recessed region 505. A portion of hardmask 512remains on a portion 511 b of surface 510 b of recessed region 505. Incertain embodiments, the etch performed on hardmask 512 at step 908,which may be referred to as an etchback, also removes hardmask 512 froma portion of surface 510 a of recessed region 505, such that at least aportion of hardmask 512 is located below top surface 508 of substrate502. In certain embodiments, the etch of hardmask 512 is performed usingany suitable combination of a wet solvent strip, a wet etch, a plasmaetch, or a UV/O₂ treatment.

At step 910, a SAM (or other surface treatment 516) is deposited on topsurface 508 of raised region 504 and on portion 511 a (or anothersuitable portion) of surface 510 b of recessed region 505, withoutdepositing the SAM (or other surface treatment 516) on hardmask 512remaining on portion 511 b of surface 510 b of recessed region 505. TheSAM (or other surface treatment 516) provides a dewetting surfacecondition (e.g., analogous to surface condition 316) for a fillmaterial, such as fill material 520.

At step 912, fill material 520 is deposited on substrate 502, by spin-ondeposition for example, such that fill material 520 fills recessedregion 505 between raised region 504 and the SAM (or other surfacetreatment 516) on portion 511 a of surface 510 b of recessed region 505without adhering to the SAM. In certain embodiments, depositing fillmaterial 520 on substrate 502 by spin-on deposition includes depositingfill material 520 on hardmask 512 remaining in recess region 505.

At step 914, the SAM (or other surface treatment 516) is removed in oneor more removal steps. This disclosure contemplates any suitable type ofremoval process for removing surface treatment 516, including anysuitable combination of a wet solvent strip, a wet etch, a plasma etch,or a UV/O₂ treatment. The removal process used to remove surfacetreatment 516 leaves fill material 520 over surface 513 of hardmask 512.In certain embodiments, an etchant used in one or more etch steps toremove surface treatment 416 and hardmask 409 is selective to surfacetreatment 516, and does not etch (or etches only a minimal amount of)fill material 520. As a result, top surface 521 of fill material 520retains its relatively planar characteristic.

At step 916, planarizing film 524 is deposited on substrate 502, byspin-on deposition for example. Planarizing film 524 may be deposited ontop surface 508 of raised region 504 of substrate 502 and on top surface521 of fill material 520. Due at least in part to the improved planarityof top surface 521 in FIG. 5D after fill material 520 has beendeposited, a top surface 526 of planarizing film 524 has improvedplanarity. Details for planarizing film 524 are described above withreference to FIG. 5E.

Following the deposition of planarizing film 524, which has improvedplanar characteristics, additional features of the semiconductor devicemay be formed in layers above or below the planarizing film. As just afew examples, these features may include metal lines, vias, or othersuitable features. Due to the improved planar characteristics of theplanarizing film, these features also tend to have improvedcharacteristics, such as improved critical dimension control andultimately improved downstream yield.

At step 918, method 900 ends.

Embodiments of this disclosure may provide one or more technicaladvantages. For example, certain embodiments reduce or eliminate a lackof planarity in a planarizing film that is deposited over a substratethat has a varied topography. By partially or completely fillingrecesses in the substrate with a fill material, the variations in thesubstrate topography may be reduced or eliminated, resulting in a morethickness-controlled planarization film when deposited over thesubstrate. Furthermore, the fill material is be directed to the recessesby applying a surface treatment to selected surfaces of the substrate(e.g., top surfaces of the substrate) prior to depositing the fillmaterial. Embodiments of this disclosure may provide some or all ofthese advantages.

Although this disclosure has been described primarily using particulartypes of substrates such as those similar to substrate 102, substrate302, substrate 402, and substrate 502, this disclosure contemplatesapplying similar principles and techniques to planarize a topography ofany suitable type of substrate. As just one particular example,embodiments of this disclosure could be applied to three-dimensionalstructures, such as substrate 202 of semiconductor device 200.

In the preceding description, specific details have been set forth, suchas a particular geometry of a processing system and descriptions ofvarious components and processes used therein. It should be understood,however, that techniques herein may be practiced in other embodimentsthat depart from these specific details, and that such details are forpurposes of explanation and not limitation. Embodiments disclosed hereinhave been described with reference to the accompanying drawings.Similarly, for purposes of explanation, specific numbers, materials, andconfigurations have been set forth in order to provide a thoroughunderstanding. Nevertheless, embodiments may be practiced without suchspecific details. Components having substantially the same functionalconstructions are denoted by like reference characters, and thus anyredundant descriptions may be omitted.

Various techniques have been described as multiple discrete operationsto assist in understanding the various embodiments. The order ofdescription should not be construed as to imply that these operationsare necessarily order dependent. Indeed, these operations need not beperformed in the order of presentation. Operations described may beperformed in a different order than the described embodiment. Variousadditional operations may be performed and/or described operations maybe omitted in additional embodiments.

Throughout this disclosure, the terms “layer” and “film” may eachinclude one or more layers or films deposited in one or more processingsteps. “Substrate” or “target substrate” as used herein genericallyrefers to an object being processed in accordance with the disclosure.The substrate may include any material portion or structure of a device,particularly a semiconductor or other electronics device, and may, forexample, be a base substrate structure, such as a semiconductor wafer,reticle, or a layer on or overlying a base substrate structure such as athin film. Thus, substrate is not limited to any particular basestructure, underlying layer or overlying layer, patterned orun-patterned, but rather, is contemplated to include any such layer orbase structure, and any combination of layers and/or base structures.The description may reference particular types of substrates, but thisis for illustrative purposes only.

Of course, the order of discussion of the different steps as describedherein has been presented for clarity sake. In general, these steps canbe performed in any suitable order. Additionally, although each of thedifferent features, techniques, configurations, etc. herein may bediscussed in different places of this disclosure, it is intended thateach of the concepts can be executed independently of each other or incombination with each other. Accordingly, the present disclosure can beembodied and viewed in many different ways.

While this disclosure has been described with reference to illustrativeembodiments, this description is not intended to be construed in alimiting sense. Various modifications and combinations of theillustrative embodiments, as well as other embodiments of thedisclosure, will be apparent to persons skilled in the art uponreference to the description. It is therefore intended that the appendedclaims encompass any such modifications or embodiments.

1. A method for processing a substrate, the method comprising: receivinga substrate having a non-planar topography including structures definingrecesses; depositing a self-assembled monolayer on top surfaces of thestructures of the substrate, without depositing the self-assembledmonolayer on surfaces located below the top surfaces of the structuresof the substrate, the self-assembled monolayer providing a dewettingsurface condition for a particular fill material; depositing theparticular fill material on the substrate by spin-on deposition suchthat the particular fill material fills the recesses without adhering tothe self-assembled monolayer; removing the self-assembled monolayer; anddepositing a planarizing film on the substrate by spin-on deposition,the planarizing film being deposited on the top surfaces of thestructures and on top surfaces of the particular fill material thatfills the recesses.
 2. The method of claim 1, wherein portions of thesubstrate include a hardmask such that the top surfaces of the portionsof the substrate are the hardmask, the self-assembled monolayer beingdeposited on the hardmask.
 3. The method of claim 2, further comprisingremoving the hardmask prior to depositing the planarizing film on thesubstrate.
 4. The method of claim 2, wherein the hardmask is a spin-oncarbon hardmask.
 5. The method of claim 1, further comprising, prior todepositing the self-assembled monolayer on the top surfaces of thestructures of the substrate: depositing a hardmask on the substrate; andetching the hardmask to remove the hardmask over the top surfaces of thestructures and from a portion of the recesses, a portion of the hardmaskremaining in the recesses.
 6. The method of claim 5, wherein depositingthe particular fill material on the substrate by spin-on deposition suchthat the particular fill material fills the recesses without adhering tothe self-assembled monolayer comprises depositing the particular fillmaterial on the portion of the hardmask remaining in the recesses. 1.hod of claim 1, wherein the self-assembled monolayer comprises: a headgroup coupled to the substrate; a functional group; and a tail groupcoupling the head group to the functional group such that that headgroup is spaced apart from the functional group, the tail group being anorganic substance.
 8. The method of claim 1, wherein the self-assembledmonolayer comprises thiol or silicon.
 9. The method of claim 1, whereinthe recesses include at least one of trenches or holes defined by thestructures of the non-planar topography of the substrate.
 10. A methodfor processing a substrate, the method comprising: applying a surfacetreatment to selected surfaces of a substrate, the substrate having anon-planar topography including structures defining recesses; depositinga fill material on the substrate by spin-on deposition, the surfacetreatment directing the fill material to the recesses and away from theselected surfaces to fill the recesses with the fill material withoutadhering to the selected surfaces; removing the surface treatment fromthe selected surfaces of the substrate; and depositing a planarizingfilm on the substrate by spin-on deposition, the planarizing film beingdeposited on the selected surfaces and top surfaces of the fillmaterial.
 11. The method of claim 10, further comprising, prior toapplying the surface treatment to the selected surfaces on thesubstrate: depositing a hardmask on the substrate; and etching thehardmask to remove the hardmask over the selected surfaces of thesubstrate and from a portion of the recesses, a portion of the hardmaskremaining in the recesses.
 12. The method of claim 11, whereindepositing the fill material on the substrate by spin-on depositioncomprises depositing the fill material on the portion of the hardmaskremaining in the recesses.
 13. The method of claim 10, wherein applyingthe surface treatment comprises depositing a self-assembled monolayer onthe selected surfaces of the substrate.
 14. The method of claim 10,wherein the recesses include at least one of trenches or holes definedby the structures of the non-planar topography of the substrate.
 15. Themethod of claim 10, wherein portions of the substrate include a hardmasksuch that the top surfaces of the portions of the substrate are thehardmask, the surface treatment being applied to the hardmask.
 16. Themethod of claim 15, further comprising removing the hardmask prior todepositing the planarizing film on the substrate.
 17. A method forprocessing a substrate, the method comprising: receiving a substratehaving a non-planar topography including a raised region and a recessedregion; depositing a hardmask on the substrate; etching the hardmask toremove the hardmask over a top surface of the raised region and from afirst portion of a surface of the recessed region, a portion of thehardmask remaining on a second portion of the surface of the recessedregion; applying a surface treatment to the top surface of the raisedregion and to a third portion of the surface of the recessed region,without applying the surface treatment to the hardmask remaining on thesecond portion of the surface of the recessed region, the surfacetreatment providing a dewetting surface condition for a fill material;depositing the fill material on the substrate by spin-on deposition suchthat the fill material fills the recessed region between the raisedregion and the surface treatment applied to the third portion of thesurface of the recessed region without adhering to the surfacetreatment; removing the surface treatment; and depositing a planarizingfilm on the substrate by spin-on deposition, the planarizing film beingdeposited on the top surface of the raised region and on a top surfaceof the fill material.
 18. The method of claim 17, wherein the thirdportion of the surface of the recessed region comprises all of the firstportion of the recessed region.
 19. The method of claim 17, wherein thehardmask is a spin-on carbon hardmask.
 20. The method of claim 17,wherein depositing the fill material on the substrate by spin-ondeposition comprises depositing the fill material on the portion of thehardmask remaining on the second portion of the surface of the recessedregion.
 21. The method of claim 17, wherein applying the surfacetreatment to the top surface of the raised region and to the thirdportion of the surface of the recessed region comprises depositing aself-assembled monolayer on the top surface of the raised region and onthe third portion of the surface of the recessed region, theself-assembled monolayer providing the dewetting surface condition forthe fill material.